Speed change mechanisms for knitting machines



March 1966 c. H. WAINWRIGHT ETAL. 3,240,033

SPEED CHANGE MECHANISMS FOR KNITTING MACHINES Filed NOV. 5, 1962 7 Sheets-Sheet 1 March 15, 1966 c. H. WAINWRIGHT ETAL 3,240,033

SPEED CHANGE MECHANISMS FOR KNITTING MACHINES Filed Nov. 5, 1962 '7 Sheets-Sheet 2 March 1966 c. H. WAINWRIGHT ETAL 3,240,033

SPEED CHANGE MECHANISMS FOR KNITTING MACHINES Filed NOV. 5, 1962 7 Sheets-Sheet 5 March 1966 c. H. WAINWRIGHT ETAL 3, ,0 3 I SPEED CHANGE MECHANISMS FOR KNITTING MACHINES Filed NOV. 5, 1962 '7 Sheets-Sheet 4.

March 1966 c. H. WAlNWRlGl-IIT ETAL 3,24

SPEED CHANGE MECHANISMS FOR KNITTING MACHINES Filed Nov. 5, 1962 7 Sheets-Sheet 5 H7 FIG7 227 W238 March 1966 c. H. WAINWRIGHT ETAL 3,240,033

SPEED CHANGE MECHANISMS FOR KNITTING MACHINES Filed Nov. 5, 1962 7 Sheets-Sheet 6 March 15, 1966 c. H. WAINWRIGHT ETAL 3,240,033

SPEED CHANGE MECHANISMS FOR KNITTING MACHINES Filed Nov. 5, 1962 7 Sheets-Sheet 7 United States Patent 3,240,033 SPEED CHANGE MECHANISMS FOR KNHTTIN G MACHINES Carlyle Herbert Wainwright and Denis John Harris,

Leicester, England, assignors to The Bentley Engineering Company Limited Filed Nov. 5, 1962, Ser. No. 235,579 Claims priority, application Great Britain, Get. 18, 1961, 37,374/ 61 3 Claims. (Cl. 66--56) This invention is for improvements in or relating to speed control mechanism for knitting machines and is concerned with mechanism for initiating speed changes as and when required to vary the speed of operation of such machines. One object of the invention is to provide speed control mechanism by which relatively short or longer periods of speed changes can be brought automatically into action effectively by a reliable and sensitive control means.

In the operation of knitting machines and particularly circular machines it is necessary for eflicieut working for the machines to be run at the highest speed practicable for satisfactory working. It follows that in the case of circular knitting machines operation is performed at high speed when uninterrupted rotary knitting takes place, but when yarn changes are necessary the speed of working must be reduced to avoid mis-feeding. Also when it is required to perform oscillatory or reciprocatory knitting as in forming heel and toe pouches of hosiery footwear, or in the case of opposed cylinder machines when transference of needles from one cylinder to the other is required to occur, or when intricate adjustment of needles is required for patterning or similar purposes is needed, a reduction in the speed of operation is necessary during these operations. When changes in operation as just referred are to take place the speed of the machine should be reduced for as short a period as possible to avoid undue loss of production.

With the advent of machines having a plurality of feeding stations spaced apart around the needle cylinder further requirements for temporarily reducing the speed of operation were introduced because of additional changes required to take place at the second and any subsequent feeding stations thus tending to complicate the problem. of providing means for effecting required speed reductions, since the period of slow speed may be needed for a complete turn of relative rotation between the needles and cam box or for only a part thereof. The invention seeks to provide means whereby the speed of the machine may be altered at any time during the knitting of a course and also for any required period, so that speed reductions can be provided for without undue loss of production.

In accordance with the invention there is provided in a circular knitting machine means through which the machine may be driven alternatively at any one of a plurality of different speed ratios, means for coupling the dirve for transmission at a selected one of the plurality of ratios, a cam shaft rotated at a constant speed, a cam on said cam shaft, and means whereby the cam may be caused to interchange connection of the driving means from one speed ratio to another under control of a sensing member operated by a timing device. The actuation of the means by which the speed reduction is obtained when required is thus derived from a cam and it can be timed to occur precisely when required and to persist for an accurately timed interval. Conveniently the means actuated by the cam comprises a pusher member which is periodically reciprocated by the cam and has its connection to the mechanism for effecting a change of speed controlled by the sensing means.

In a preferred arrangement there are a plurality of t1ming devices each having sensing means: which control means operated from the said cam shaft whereby the same mechanism for effecting a speed change can have its operation initiated by any of the timing devices. Such an arrangement is particularly applicable to control of a two or three feed circular knitting machine. In the case where the operation of the speed changing means is effected by means of a pusher member from the cam shaft, there will be a plurality of pusher members associated with a common speed change actuating member to operate the latter and each pusher member conveniently has associated with it a separate cam on the cam shaft, the several pusher members being controlled respectively by a plurality of timing devices to bring them into active cooperation with the speed change actuating member. The several timing devices may be arranged to provide for speed reductions to occur for changes from rotary to reciprocatory knitting, yarn changes at different feeding stations, changes in needle set up etc.

In carrying out the invention there is preferably also provided a form of catch mechanism for retaining the setting of the speed changing means at an altered setting for a predetermined prolonged interval. Such catch mechanism may be controlled from a main control drum of the machine.

Certain particular examples of speed control mechanism as provided by the invention for use on a three feed circular knitting machine will now be described in detail with reference to the accompanying drawings in which only parts of the machine necessary for an understanding of the mechanism are shown. In the drawings:

FIGURE 1 is a side view of the mechanism shown in relation to part of the frame of the machine,

FIGURE 2 is a plan view of parts shown in FIGURE 1 and shows also in a general manner additional units of the control mechanism arranged in a bank,

FIGURE 3 is a view of certain details of the belt shipper mechanism seen in the direction of the arrow C in FIG- URE 1,

FIGURE 4 is a plan view on a larger scale of the bank of additional units of the control mechanism shown generally in FIGURE 2, and parts related to them,

FIGURE 5 is an end view of parts shown in FIG- URE 4,

FIGURES 6, 7 and 8 are views corresponding to a part of FIGURE 1 but on a somewhat larger scale showing somewhat diagrammatically a modified arrangement with the parts in different settings in these three figures,

FIGURE 9 is an enlarged perspective view in detail of certain of the parts appearing at the bottom right hand portion of FIGURE 1 as viewed from a point somewhat to the right of FIGURE 1, and

FIGURE 10 is an enlarged perspective view of certain of the parts shown in FIGURES 4 and 5.

The drive to the needle cylinder or cylinders is not shown in the drawings as it is not a necessary factor in the understanding of the speed control mechanism. It is sufficient to explain that there are three different speeds available and each speed is obtained by shipping a belt to the appropriate one of three pulleys provided. Each pulley drives the cylinders through a different chain of gears to produce fast, medium and slow speeds. An idle pulley is not provided as there is a friction type clutch interposes between the source of power and the single belt driving pulley (not shown).

In FIGURE 2 the three pulleys are identified by the numbers 1, 2 and 3, being fast, medium and slow respectively, the driving shaft Ia and sleeves 2a and 3a which connect them to their respective gears being shown broken and their gears being omitted for the sake of clarity. The needle cylinder which the pulleys drive is shown at 4 in FIGURE 1; it is mounted on a bearing in a bedplate 5 which is carried by frame 6 as is customary in this type of machine. A main control drum 7 on a shaft 11 is given step by step movements by racking mechanism acting upon a rack wheel 8 which is secured to the drum 7. The racking mechanism is not shown as it may be of any conventional type arranged to transmit step by step movement to the rack wheel 8 from suitable cams carried by a main cam shaft 9.

A sprocket 10 is carried on the drum shaft 11 and carries a main chain 12. The main chain is of conventional type and is provided on both edges of the links with studs or cams such as 13 and 14, spaced throughout the length of the chain according to the type of knitted article required to be produced.

The studs 13 on one side of the chain 12 (appearing on the left in FIG. 4) are used for initiating racking of the drum 7, and the studs 14 on the other side are used for producing changes of yarn at the main feed station. As it has been found advisable to slow the machine speed in order to rack the main drum as well as to make yarn changes, the studs 13 and 14 may also be made use of to operate the speed change mechanism at the same time as they initiate their respective racking and yarn changing operations. The means for shipping the belt to accomplish the speed change is shown in FIGS. 1 and 2.

FIGURE 1 shows only the speed control mechanism associated with chain studs 13 used for drum racking. The mechanism for changing speed to suit the yarn changes and also further mechanism for changing speed to suit other functions is merely a repeat of the one shown in FIG. 1, the complete set of controls forming a bank as indicated generally by the chain dotted lines 15 in FIG. 2.

Referring to FIGS. 1 and 2 the sprocket wheel 10 is attached to a rack wheel 18. The sprocket wheel and chain are moved or racked to the extent of half one chain link for every revolution of the needle cylinder by racking mechanism (not shown) acting upon the rack wheel 18. It should be mentioned that this racking mechanism is quite separate from the aforementioned mechanism provided for racking the main drum 7, the sprocket wheel assembly and the main drum assembly being quite independent of one another although mounted to turn on a common axis.

FIG. 1 shows a lever 16 movable about pivot 19 to which is attached a follower 17 positioned on top of a chain stud 13, the sprocket wheel 10 being caused to be racked in the direction of arrow A. The stud 13 may be one of two different lengths, namely a full length stud which is equal in length to one chain link or a half length stud equal in length to half a chain link. When the follower 17 of the lever 16 is raised by a stud as shown in FIG. 1 it depresses a rod 21 having an upper end which is slidably located in two supports 22 and 23 which are attached to the wall of the frame of the machine. The rod 21 rocks a bell-crank lever 24 in an anti-clockwise direction about its fulcrum 25 to the position shown, thus causing a bar 26 to which it is attached, to slide over a supporting pin 27. A cam slope 28 formed on the bar contacts a lug 23 of a bluff lever 30 which is fulcrumed on the pin 27. The lug 29 is lifted by the cam slope thus causing the bluff lever to pivot in a clockwise direction about its fulcrum and its nose portion 31 to be lowered. In brief then, when the follower 17 is raised by a chain stud 13 the nose 31 of the bluff lever 36) is lowered to the position indicated by the unbroken lines in FIG. 1.

The broken lines 31a show the position of the nose of the bluff lever when the follower is off the stud. In this position the nose 31a is shown supporting a member 32 in a raised position at 32a (also indicated by broken lines). Member 32 is carried by a post 33 which is secured in the wall of the frame. The member 32 is free to pivot and also to slide to a certain extent upon the post 33 as can be seen in FIG. 1. It is shaped at one end to form a follower which contacts the periphery of a disc cam 34 to which it is urged by a spring 135. The other end of the member 32 is stepped to provide a latchlike abutment.

With the member 32 supported by the nose 31a of the bluff lever 31 as shown by broken lines in FIG. 1, the disc cam 34 (which is mounted on the shaft 9 and is revolving constantly whilst the machine is in motion) will cause the member 32 to slide to and fro idly. When the bluff lever 30 is lowered by a chain stud 13 being advanced under the follower 17, the member 32 will be lowered to the position shown by the unbroken lines in FIG. 1 where its latch-like abutment engages with a cross bar on a U-shaped component 35 associated with the mechanism by which the belt is shifted from one pulley to another. This mechanism will now be described.

The component 35 is mounted for pivoting motion on a stub spindle 36 which is secured to and projects from a wall of the frame. A torsion spring 38 is also carried on the spindle 36, to which it is anchored at one end by means of a screw and collar 39. The spring 38 is pre loaded to press upon the U-shaped component 35 to urge it (in a clockwise direction as viewed in FIG. 1) into contact with a roller 41]) which is mounted on a spindle secured in a flat triangular shaped plate 41. The plate 41 is itself mounted for pivoting action on a spindle 42 secured in a bracket 43 which is fixed to the wall of the frame as can be seen in FIG, 2. The apex 41a of the plate 41 is located in a slot formed in an end of a shaft or rod 44 which is slidably mounted in holes in lugs 45 projecting from the rear of the side walls of the frame. The slot in the end of the rod 44 houses a roller 46 which is carried on a spindle 47 secured in the walls of the slot. Attached to the spindle 47 is a tension spring 48 the other end of which is anchored to the far wall of the frame at a point 49, FIG. 2.

From the construction just described it can be seen that the spring 48 will urge the rod 44 to slide in the lugs 45 of the frame. The roller 46 will contact the apex 41a of the triangular shaped plate 41 and will rock the plate about its spindle 42 thus causing the roller 40 to bear on the U-shaped component 35 and swing it towards an upright position against the action of the torsion spring 38. By reference to FIG. 3 the disposition of the components associated with the rod 44 can more easily be seen.

Two rods 51 secured in a block 52, straddle the belt 53 to guide it from one pulley to another. The block 52 is secured to the rod 44 in such a position that the belt is guided on to the fast speed pulley when the rod 44 is pulled to the extreme position by the spring 48 with the stop pin 51 up against the wall of the frame. Two steps 54 and 55 cut in the rod 44 are provided to cooperate with a catch consisting of a flat plate 56 which is pivotally mounted on a spindle 57 which is secured in the wall of the frame. FIG. 3 shows this plate 56 engaged with the step 54. This will retain the rod 44 and belt guide assembly 51 and 52 in position to direct the belt on to the middle pulley 2 to drive the machine at medium speed.

The catch plate 56 is operated by a rod 58, FIGS. 1 and 3, which is located in a hole in the plate and retained by a nut 59. A compression spring 60 is assembled on the rod which is then slidably located in a hole in one end of a horizontal lever 61 and retained therein by two locknuts 62. The lever 61 is mounted on a spindle 63 carried in the wall of the frame. The other end of the lever 61 (which is of bell-crank form) is shaped as a cam follower 61a which as can be seen in FIG. 1 is arranged to cooperate with cams such as 64 and 65 carried by the main control drum 7. By appropriate actuation of the follower 61a, the catch plate 56 can be raised and lowered to the heights necessary for engagement with the steps 54 and 55 in the rod 44 and disengagement from the rod.

From the foregoing description it can be seen that there are basically four interconnected mechanisms which together comprise the means so far described for changing the speed of the machine. Briefly reviewing these four mechanisms we have:

(1) A constantly revolving cam and associated member which is constantly reciprocating.

(2) A control from a chain stud by which the reciprocating member can be lowered to an operative position.

(3) Belt shipping mechanism which is activated by the reciprocating member when said member is lowered.

(4) Catch mechanism, under the control of the main drum, for retaining the belt shipping mechanism, if required, in the position to which it is moved by the reciprocating member.

An example of how a change of speed is accomplished will now be described. Consider the machine to be running at fast speed with the belt on pulley 1 and with the shipping rod 44 in an extreme position with the stop pin 56 held against the wall of the frame by the spring 48. The main chain is being racked one half link per revolution of the needle cylinder and when a speed change is desired a link with a stud 13 operates to lift the follower 17 which will immediately lower the nose 31 of the bluff lever thus allowing the member 32 to contact the cross bar of U-shaped component 35. If the cam 34 is in such a position at this moment, that the cam follower end of member 32 is resting in a trough of the cam 34 (FIG.

1), its abutment will obviously be moved to engage component 35 as soon as the slope 34a of the cam contacts it. If, however, the cam 34 is positioned with the member 32 resting on its top diameter at the moment the bluff lever nose 31 is lowered, the member 32 will be lowered with its abutment beyond and out of engagement with the cross bar of component 35. No actuation of component 35 will occur until after cam 34 has rotated sufiiciently to allow the member 32 to move back into a trough after which the abutment will be able to engage and actuate component 35 as the member 32 is moved forward again by the slope of the cam.

When the component 35 is rocked in a clockwise direction (FIG. 1) by member 32, the belt shipper rod 44 will be displaced axially against the spring 48 to an extent controlled by the diameter of the cam 34. This displacement could be to either one of the positions necessary to align the belt with the medium speed pulley 2 or the slow speed pulley 3, thus changing the speed of the machine. Now, unless the catch mechanism previously described is operated, the new speed will only be maintained whilst the member 32 is riding on the top height of earns 34 because immediately the cam has revolved sulficiently to allow the member 32 to move back into a trough of the cam then the belt shipper rod 44 will be sprung back to its original position to move the belt back to the fast speed pulley.

If it is desired to retain the belt on either of the slower speed pulleys 2 or 3 then the catch plate 56 must be operated by controls previously described from the main drum 7. This catch plate mechanism is of the type which is primed that is to say it can be preloaded by a rack of the main drum at a convenient period before the change of speed is initiated by a stud on the main chain. Thus when the drum 7 is racked, a cam 54 or 65 is advanced under the follower 61a of the bell crank lever 61. The cams 64 and 65 are two different heights, thus there are three different positions for the follower 61a viz: bottom height on the surface of the drum, a medium height on cam 64 and a top height on cam 65. The corresponding positions of the catch plate are: low to engage the second step 55 partly lifted to engage the first step 54, and fully lifted clear of the rod 44.

The priming of the catch plate 56 is obtained by the action of a spring 61b which urges the catch plate 56 down on to rod 44 when the cam 64 or 65 is racked from under the follower 61a. The catch plate is thus primed 6 so that it will engage the appropriate stop 54 or 55 inimediately upon displacement of the rod 44 to the required slower speed position and will retain the. rod with the belt on the required pulley.

The timing of speed changes with respect to different angular positions of the needle cylinders is obtained simply by adjusting the angular position of the cam 34 on the shaft 9. As the cam 34 is rotated once for every two revolutions of the needle cylinders a single trough cut in the cam can produce a change of speed once only in two revolutions of the needle cylinders. By having the cam formed with two troughs spaced apart, a change of speed can be produced once in each revolution of the needle cylinders. Similarly speed changes at shorter intervals can be arranged by substitution of cams having three or more spaced troughs.

A change of speed can only occur when the follower 17 is raised by a stud of the chain, and, unless the catch mechanism is operative, a reverse change will occur when the stud allows the follower to drop. If the stud is a full length one the follower will be lifted for two revolutions of the needle cylinders, whereas if the stud is a half length one the follower will be lifted only for one revolution of the needle cylinders. The half length studs may be provided either at the front half or the back half of the chain link; thus the follower 17 can be lifted on the first or the second of two revolutions of the needle cylinder or the first or second half turn of the cam 34.

From the above it will be realised that there are a number of combinations of cams such as 34 and studs such as 13 which together can produce changes of speed at any required time and when coupled with the catch mechanism the change of speed may be maintained for any period. It should be noted that the length of a stud and its position on the chain link are dictated by the primary function of the stud. For instance, a full length stud on one side of the chain is primarily intended to initiate a rack of the main drum and a back half stud situated on the other side of a link is primarily intended to initiate a yarn change on the second of two revolutions of the needle cylinder. It is appropriate, therefore, that the cam 34 shall be designed and adjusted to suit the requirements of speed changes to be derived from the particular row of studs related to it.

The means for changing speed to suit the functions performed under the control of the main chain having now been described, it will readily be appreciated that similar mechanism may be used to initiate speed changes to suit other functions, such as auxiliary feeding at second and third stations, which are themselves under the control of auxiliary pattern chains. The controls from three auxiliary chains are shown in detail in FIGS. 4 and 5 and their position with respect to the main chain controls 1s indicated in a general way by the broken lines 66 in FIG. 2. As mentioned previously the actual belt shipping mechanism is common to the controls from all the chains, the U-shaped component 35 being wide enough to co-operate with a number of levers similar to the one indicated at 30 in FIG. 1. A bank of these levers is indicated generally at 15 in FIG. 2 and each one is operated by similar mechanism to that previously described as being associated with the rod 21 shown in FIG. 1. As can be seen in FIGS. 2 and 4 the posts 22 and 23 have holes to accommodate four rods. The first hole is shown in FIG. 4 without its rod 21, this rod and its associated parts being omitted from this view for the sake of clarity. Three other rods 67, 68 and 69 are each operated by controls which are carried by a bracket secured to the side of the frame. These controls will now be described with reference to FIGS. 4 and 5.

The bracket just referred to has two walls 70 and 71 which are mounted on a sleeve which carries the main chain assembly and on a rod 72 which projects from the side of the frame. Freely mounted on the sleeve are three auxiliary chain wheel assemblies, each comprising a chain carried by a sprocket wheel to which is attached a rack wheel, these assemblies being shown at 73, 74 and 75 in FIG. 4. Each assembly has its own racking mechanism (not shown) which is brought into action when required by a cam on the main drum. The chain assembly 73 is used in conjunction with the main chain 12 to pro vide another control for operating yarn changes at the main feeding station. This second control is convenient for obtaining a repetition of yarn changes to produce repeated patterns of horizontal stripes. Chain assembly 74 is used to control yarn changes at a third feeding station and assembly 75 is used to control yarn changes at a second feeding station. The actual controls to the yarn change mechanisms have been omitted from the drawings as they would confuse with the controls leading to the speed change mechanism.

Referring to FIG. 4, two axially aligned tubes 76a and 76b are shown projecting to the right and left of a U- shaped component 77 to which they are fixed. One leg of component 77 projects at right angles from the tube 76b and is shaped into a nose 77a. This nose is shown in FIG. 4 contacting a lever 78 which is mounted on a spindle 79 secured in the wall of the frame. The tubes 76a and 7611 house a shaft 80 to which is clamped by a screw 81 a lever 82 having a nose 32a. This nose is shown in FIG. contacting a lever 83 which is also mounted on the spindle 79. The tube 76b is freely mounted in a bearing bracket 84 attached to the bed plate, whilst at the other end the tube 76a is supported by the shaft 80 which is freely mounted in the wall 70 of the bracket. A collar 85 and a cam follower 86 are clamped to the tube 76b on either side of the bracket 84 and locate the tube and shaft assembly axially. A cam follower 87 is clamped to an end of the shaft 80 adjacent the cam follower 86 whilst at the other end of the shaft a forked lever 88 is secured. A similar forked lever 89 is secured to the end of the tube 7 6a adjacent lever 88.

Altogether there are six levers carried by the combined tubes and shaft, these are: cam follower 87, lever 82 and forked lever 88, all fixed to the shaft 80, and cam follower 86, lever 77 and forked lever 89, all fixed to the tubes 76a and 76b. The levers associated with the tubes are concerned with operating the rod 67 and those associated with the shaft are concerned with operating the rod 68. The forked lever 89 is connected by a link 90 to a bell crank lever 91 provided with a cam follower 91a (see FIG. and in similar manner the forked lever 88 is connected by a link 92 to a bell crank lever 93 provided with a cam follower 93a (see FIG. 5). The bell crank levers 91 and 93 are freely mounted on a shaft 94 which is secured in the walls 70 and 71 of the bracket. The levers are spaced apart by collars such as 95 (FIG. 4); cam followers 91a and 93a cooperate with the chain studs of assemblies 74 (see FIG. 10) and 75 (see FIG. 5) respectively.

It can thus be seen that the rod 67 can be depressed to bring about a change of speed, by the action of a stud of chain assembly 74, or by the action of a drum cam on follower 86. In similar manner the rod 68 can be depressed to bring about a change of speed, by the action of a stud of chain assembly 75, or by the action of a drum cam on the follower 87.

The rod 69 is the one provided to produce speed changes to suit yarn changes at the main feeding station. This rod is operated by both the auxiliary pattern chain assembly 73 and the main chain 12 in the following manner.

A shaft or spindle 96 (FIG. 4) is mounted freely in the walls 70 and 71 of the bracket, being retained therein by collars 97 and 98 secured to the spindle. Two levers 99 and 108 are also fixed to the spindle. The lever 99 is forked and is connected by a link 181 to a bell crank lever 102 which is freely mounted on the shaft 94 (see FIG. 5). The lever 102 is provided with a nose 102a to operate from studs of chain assembly '73 (see FIG. 10). The lever 180 is fixed between its ends to the spindle 96 and is provided at one end with an adjusting screw 103 and locknut 104. The head of the screw is shown in FIG. 5 contacting the top of the rod 69. At its other end the lever is formed into a nose or follower 188a to operate on studs provided on the right hand side of the main chain 12 (as seen in FIG. 5). As both the levers 99 and are fixed to the spindle 96 it is obvious that the studs of both chains will be capable of initiating a speed change through the medium of the single rod 69.

From the foregoing description it is apparent that there is provided two means to control speed variations for feeder changes at each of the three feeding stations. Briefly, these are:

(1) At the main or first feeding station, a control from the main chain and also acontrol from an auxiliary chain (assembly 73, FIG. 4) for striping sequences.

(2) At the second feed station, a control from the drum 7 and also a control from an auxiliary chain (assembly 75, FIG. 4) for striping sequences.

(3) At the third feed station, a control from the drum 7 and also a control from an auxiliary chain (assembly 74, FIG. 4 )for striping sequences.

In a modified arrangement of the mechanism shown diagrammatically in different positions in FIGS. 6, 7 and 8 a bluff lever 230 replaces the bluff lever 30 and is pivotally connected at 231 to the right hand end of a bar 226 replacing the bar 26. The bluff lever 230 is acted on by a return spring 227 and its nose cooperates with the member 32 as described in connection with the first form of construction the latter being acted upon by a cam 234.

In the construction of FIGS. 6 to 8 there is also provided modified catch mechanism comprising a prop lever 237 pivoted at 27 and fitted with a return spring 238, and having a turned over ear 237a which cooperates with an arm 230a of bluff lever 230. The prop lever 237 cooperates with a double armed catch lever 236 freely pivoted on spindle 33 and urged to turn in a clockwise direction by a spring 232. The lever 236 is not movable endwise like the member 32 but it has a step 236/5 near its right hand end corresponding to the step indicated at 132 on member 32 to cooperate with the cross bar on U- shaped component 35. The other end of lever 236 is indicated at 236a and forms a follower engaging with a cam 235 which like the cam 234 is mounted on the main cam shaft 9. The cam 235 is of circular concentric form with a cam hump 235a.

The parts 237, 236 and 235 can be employed in place of the catch plate 56 and related parts of the earlier construction to retain the belt shipper rod 44 in one of the slower speed positions for a timed interval. Normally when the machine is operated at a fast speed the bluff lever 230 is held raised so member 32 reciprocates idly without actuating the U-shaped component 35. The prop lever 237 is at the same time engaged under a step 2360 on the lever 236 and holds the right hand end of the lever raised. When the rod 21 is depressed the bluff lever 230 will be rocked downwardly and by engaging the ear 237a will rock the prop lever 237 to disengage it fro-m the lever 236. The lowering of the nose of bluff lever 230 causes the member 32 to drop into engagement with the U-shaped component 35 and operate the latter in the manner previously described to move the belt shipper rod 44 so as to reduce the speed of drive. Thereupon the lever 236 will also drop into engagement with the U- shaped component 35 and hold it in the position to which it has been swung by the member 32. This position of the parts is shown in FIG. 7.

With continued rotation of the cam shaft the hump 235a of cam 235 will pass follower 236a before the member 32 rides off the raised part of cam 234 so by the time the member 32 is released and permitted to move to the left the lever 236 will have its stepped portion 2361) engaged with the U-shaped component 35 to maintain the latter in its operated position. At this stage the parts will be positioned as shown in FIG. 8. The U-shaped component 35 will continue to be deflected to its operated position until at the next turn of the cam shaft the cam hump 235a will rock the lever 236 to release its stepped part 236k from the U-shaped component. This also causes its step 236c to ride past the prop lever 237 permitting the latter to swing back to its initial position and hold the lever 236 in raised setting. The U-shaped component is thus at this time returned under spring action to its initial position causing the belt shipper rod 44 to return the belt to the pulley for operating the machine at fast speed.

The timing of the delayed return of the belt shipper rod 44 is thus dependent on the setting of cam 235 on the cam shaft and not on any racking movement of the pattern drum 7.

What we claim is: j

1. Speed control mechanism for a circular knitting machine which comprises:

(a) a plurality of rotary driving members for operating the machine at different speeds;

(b) means for coupling said rotary driving members alternatively to a driven shaft for operating the ma chine;

(c) speed adjusting means for transferring the coupling from one driving member to another;

(d) catch means for retaining the setting of the speed adjusting means at a desired setting for a predetermined prolonged interval;

(e) a timing cam to release the catch means when desired;

(f) a sensing member;

(g) timing means for actuating the sensing member;

(h) a driven cam shaft;

(i) a cam on said cam shaft; and

(l) means whereby the cam operates the speed adjusting means under the control of the sensing member.

2. Speed control mechanism for a circular knitting machine which comprises:

(a) a plurality of rotary driving members for operating the machine at different speeds;

(b) means for coupling said rotary driving members alternatively to a driven shaft for operating the machine;

(c) a sensing member;

(d) timing means for actuating the sensing member;

(e) a pivotstud;

(f) a pusher member mounted for sliding and pivoting movement on the pivot stud;

(g) a bluffing member for rocking the pusher member into an inactive setting;

(h) means actuated by the sensing member to move the bluffing member to release the pusher member;

(i) speed adjusting means for transferring the coupling from one driving member to another which comprises a lever cooperating with the pusher member, whereby release of the pusher member will actuate the lever to effect speed change;

(i) a driven cam shaft;

(k) a cam on said calm shaft; and

(1) means whereby the cam operates under the control of the sensing member to release the pusher member.

3. Speed control mechanism for a circular knitting machine which comprises:

(a) a plurality of rotary driving members for operating the machine at different speeds;

(b) means for coupling said rotary driving members alternatively to a driven shaft for operating the machine;

(c) speed adjusting means for transferring the coupling from one driving member to another;

(d) a sensing member;

(e) timing means for actuating the sensing member:

(f) a driven cam shaft;

(g) a cam on said cam shaft;

(h) a pusher member actuated by the cam so as to be periodically restricted thereby; and

(i) a U-shaped pivoted member having a cross bar, whereby said pusher member cooperates with the cross bar to operate the pivoted member for effecting a speed change.

4. Speed control mechanism according to claim 3 which comprises:

(a) a plurality of pusher members;

(b) a plurality of sensing members associated respectively therewith; and

(c) a U-shaped pivoted member common to all of the pusher members and operated by any one of them.

5. Speed control mechanism for a circular knitting machine which comprises:

(a) a plurality of rotary driving pulleys for operating the machine at different speeds;

(b) a belt for coupling the pulleys alternatively to a driven shaft for operating the machine;

(0) a belt shipper rod movable endwise for effecting speed changes by transferring the belt from one to another of the driving pulleys;

(d) a triangular lever pivoted at one corner and having one of its other corners in engagement with the belt shipper rod;

(e) a speed adjusting lever means for operating the belt shipper rod which comprises a U-shaped lever having a cross member which engages the remaining corner of the triangular lever;

(f) a sensing member;

(g) timing means for actuating the sensing member;

(h) a driven cam shaft;

(i) a cam on the cam shaft; and

(l) means controlled by the sensing member for causing the cam to operate the speed adjusting lever means to effect a speed change.

6. Speed control mechanism for a circular knitting machine which comprises:

(a) a plurality of rotary driving pulleys for operating the machine at different speeds;

(b) a belt for coupling the pulleys alternatively to a driven shaft for operating the machine;

(c) a belt shipper rod movable endwise for effecting speed changes by transferring the belt from one to another of the driving pulleys;

(d) a triangular lever pivoted at one corner and having one of its other corners in engagement with the belt shipper rod;

(e) a speed adjusting lever means for operating the belt shipper rod which comprises a U-shaped lever having a cross member which engages the remaining corner of the triangular lever;

(f) a sensing member;

(g) timing means for actuating the sensing member;

(h) a pusher member having a notch engageable with the U-shaped lever;

(i) a driven cam shaft;

(j) a cam on the cam shaft; and

(k) means controlled by the sensing member for causing the cam to operate the speed adjusting lever means to effect a speed change.

7. Speed control mechanism for a circular knitting machine which comprises:

(a) a plurality of rotary driving members for operating the machine at different speeds;

(b) means for coupling the rotary driving members alternatively to a driven shaft;

(c) speed adjusting means for transferring the coupling from one driving member to another;

(d) a plurality of sensing members;

(e) a plurality of timing means for respectively actuating the sensing members;

1 1 l 2 (f) a driven cam shaft; (h) cams on said cam shaft related respectively to said (g) cams on said cam shaft related respectively to said sensing members; and

sensing members; and (i) separate means controlled by each of the sensing (h) means whereby any of said cams is caused to opmembers for causing the related cam to operate the erate the speed adjusting means under the control of the appropriate sensing member.

speed adjusting lever means to effect a speed change.

8. Speed control mechanism for a circular knitting ma- References Cited y the Examine! fi il RP d n d t UNITED STATES PATENTS p y rotary rlvlng P @ys Operate a 479,986 8/1892 King dlfierent Speeds 10 1463 40s 7/1923 s t 66 56 (b) a belt for coupling said pulleys alternatively to a Z 2,587,816 3/1952 Br1st0w 6656 driven shaft for operating the machine, 2 697 337 12/1954 B 1 66 56 (c) a belt shipper rod movable endwise for effecting 3010299 11/1961 fi et 6656 speed changes by transferring the belt from one to annon W another of the driving pulleys; 15 FOREIGN PATENTS (d) speed adjusting lever means for operating the belt 33 4 266 9/1930 Great Britain shipper rod; l

a p y members; DONALD W. PARKER, Primary Examiner. a p ura ity o timing means for respectively actuating the Sensing members; 20 RUSSELL C. MADER, Examiner.

(g) a driven cam shaft; R. FELDBAUM, Assistant Examiner. 

1. SPEED CONTROL MECHANISM FOR A CIRCULAR KNITTING MACHINE WHICH COMPRISES: (A) A PLURALITY OF ROTARY DRIVING MEMBERS FOR OPERATING THE MACHINE AT DIFFERENT SPEEDS; (B) MEANS FOR COUPLING SAID ROTARY DRIVING MEMBERS ALTERNATELY TO A DRIVEN SHAFT FOR OPERATING THE MACHINE; (C) SPEED ADJUSTING MEANS FOR TRANSFERRING THE COUPLING FROM ONE DRIVING MEMBER TO ANOTHER; (D) CATCH MEANS FOR RETAINING THE SETTING OF THE SPEED ADJUSTING MEANS AT A DESIRED SETTING FOR A PREDETERMINED PROLONGED INTERVAL; (E) A TIMING CAM TO BE RELEASE THE CATCH MEANS WHEN DESIRED; (F) A SENSING MEMBER; (G) TIMING MEANS FOR ACTUATING THE SENSING MEMBER; (H) A DRIVEN CAM SHAFT; (I) A CAM ON SAID CAM SHAFT; AND (J) MEANS WHEREBY THE CAM OPERATES THE SPEED ADJUSTING MEANS UNDER THE CONTROL OF THE SENSING MEMBER. 